Getting Started: C# Interview Questions

Technical interviews for junior C# developer roles rarely focus on complex architecture; instead, they strictly test your grasp of the language fundamentals and how the .NET runtime actually handles your code. This course prepares you for those exact conversations by walking through the core concepts you are guaranteed to be asked about. You will start with the essentials, covering types, variables, strings, and type casting, before moving into control flow, loops, and method overloading. From there, we cover object-oriented programming in C#, ensuring you can clearly explain encapsulation, inheritance, polymorphism, and the practical differences between abstract classes and interfaces. Because interviewers consistently probe your understanding of memory, we dedicate an entire module to the differences between value and reference types, the stack and the heap, boxing and unboxing, and how a struct compares to a class alongside garbage collection basics.

With memory management understood, you will explore collections and generics, learning exactly when to use an array, List, Dictionary, Queue, Stack, or HashSet, and how to apply generic constraints. Next, we cover LINQ fundamentals, focusing heavily on deferred execution, filtering, projection, ordering, and aggregation. You will also learn how to properly handle errors using try, catch, and finally blocks, alongside best practices for throwing and building custom exceptions. We then break down delegates, events, and lambdas, including the built-in Func, Action, and Predicate types. Finally, the course addresses modern C# development by explaining Tasks, the async and await keywords, and the common asynchronous pitfalls you need to avoid. We wrap up by examining the .NET platform itself, discussing the CLR, compilation, null-safety, properties, and specific language features like const, enum, and record types.